CANOGA PERKINS 2345 T3 Fiber Optic Modem - Manual (Page 32)

EdgeAccess Universal Chassis System
Model 2345 User Manual 4-2
Note: For accurate results, warm up each unit for at least 30 minutes before checking power levels.
The transmission laser in a 2345 turns on automatically when the chassis receives power.
To measure the output power, follow these steps:
1. Clean the connectors on the fiber optic test cable before plugging it in to the Tx connector on
the 2345.
2. Warm up each component for at least 30 minutes.
3. Set the optical power meter to the proper wavelength.
4. Wait two or three minutes for the power reading to stabilize, and then read the output power.
5. Subtract out the test cable loss, then record the power level and compare it to the value on the
performance sheet for that particular 2345. Measurement tolerance is +/- 0.5 dBm.
Note: When referencing optical power levels with numerical values less than zero, the reading
closer to zero is the greater value; for example, -17 dBm is greater than -20 dBm.
6. If the reading is incorrect, repeat the measurement with a different test cable. If the power level is
still not within range, call Technical Support.
If you know the link attenuation, subtract that value from the 2345 Tx output value to determine the
power expected at the remote cable end, which is the input power at the remote receiver, and skip this
section. Otherwise, continue these steps to use the 2345 to measure the link attenuation.
7. At the local site, connect the fiber link cable to Tx on the 2345.
8. At the remote site, set the optical power meter to the proper wavelength and connect it to the fiber
link cable.
9. Record the optical power level and compare it with the sensitivity level listed on the data sheet
for the link fiber type.
10. Subtract the remote power level from the value for the transmitter output power at the local site.
The result provides the link loss, in dB. This power level must not exceed the limit for Rx
sensitivity listed on the data sheet for the remote unit.
Note: If you cannot determine the Rx sensitivity, contact Canoga Perkins Technical Support
Department for assistance.
11. Repeat this process at the other site.
Troubleshooting
This section describes fault conditions and corrective action. As a rule, whenever there is a
significant signal loss, check the fiber path and the minimum bend radius for potential problems.
Remove and inspect the cable connectors, being careful not to damage the fiber end-face surface or
the connector housing. Clean all optical connectors before reinstalling them.